Alcohol and Liver Disease

Critique 028. Changes over time in relation of social class to mortality from cirrhosis.9 January 2011

Reference: Crombie IK, Precious E. Changes in the social class gradient of cirrhosis mortality in England and Wales across the 20th century. Alcohol and Alcoholism 2011;46:80–82.

To explore the nature of the social class gradient of cirrhosis mortality in England and Wales across the 20th century, data on male cirrhosis mortality by social class were obtained from the Registrar General’s Decennial Supplements for the years 1921–1991. This paper describes a dramatic change during the 20th century in the association between social class and mortality from liver cirrhosis. While deaths from cirrhosis were more common among higher social classes in the early part of the century, the pattern changed so that deaths from cirrhosis were much more common among the lower social classes by the end of the century.

Suggested reasons for the lower current rates among subjects at higher social class include different patterns of alcohol consumption, with regular moderate consumption (especially of wine with meals) becoming more common with higher social class subjects while binge drinking (especially of beer and spirits) remaining more common in lower social classes. However, a number of other factors may relate to the class differences in rates of hepatic cirrhosis, including a less healthy diet and greater rates of obesity (associated with hepatic fatty liver and cirrhosis) among lower social class subjects and social class differences in hepatitis rates. Further, certain medications, coffee consumption, and many other lifestyle factors are associated with hepatic cirrhosis. The actual reasons for the changes over time reported in this paper remain unclear.

A new meta-analysis shows that alcohol consumption is a strong factor in the development of cirrhosis of the liver. The study also supports the theory that there is a threshold of drinking above which the risk is increased, as some of their analyses suggest that the risk increases only with intake of more than 24 grams/day of alcohol for women (about 2 typical drinks by US standards) and 36 grams/day of alcohol for men (about 3 typical US drinks).

Despite some concerns about the approach used, our Forum agrees that the present meta-analysis supports previous studies indicating a strong role of heavy alcohol drinking in the development of cirrhosis. The differences found by the investigators between the effects of moderate alcohol intake on cirrhosis morbidity and on cirrhosis mortality are difficult to explain, but may relate to misclassification of alcohol intake (heavy drinkers reporting less alcohol), always a problem in observational studies of the effects of alcohol.

The results related to morbidity suggest that small amounts of alcohol are not associated with an increased risk of cirrhosis, and may be associated with lower risk of disease. Thus, the data provide evidence for a “threshold effect” of alcohol intake for the development of cirrhosis. Limited previous data are available suggesting that wine consumption may be associated with lower risk of cirrhosis than the intake of other beverages, but essentially all studies show heavy drinking of any type of beverage increases the risk.